body{
  background-image: url("../imgs/bgd.jpg");
}
.out{
  width: 1495px;
  height: 200px;
  background-color: black;
  margin-top: 200px;
  margin-left: 35px;
}
.out li{
  float: left;
  margin-right:10px ;
  margin-top: 20px;
  background-color: pink;
}
.down{
  width: 1000px;
  height: 200px;
  background-color: black;
  margin-top: 50px;
  margin-left: 40px;
}
.down li{
  margin-top: 20px;
  width: 110px;
  height: 160px;
  background-color: pink;
  float: left;
  margin-right:20px ;
}
button{
  margin-left: 90px;
  margin-top: 70px;
  width: 100px;
  height: 50px;
  background-color: yellow;
  font-size: 30px;
  font-family: '幼圆';
}
.back{
  width: 100%;
  height: 100%;
}